WinRAR cannot modify locked archives, so locking important archives prevents their accidental modification by WinRAR. Such protection might be especially useful in case of WinRAR commands processing archives in groups.
This command is not intended or able to prevent modification by other tools or willful third party. It implements a safety measure only for accidental data change by WinRAR.
This is the command line equivalent of the archive management command Lock archive. It is supported for RAR archive format only.
Example
WinRAR k release